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Papadakis S, Thompson JR, Feczko E, Miranda-Dominguez O, Dunn GA, Selby M, Mitchell AJ, Sullivan EL, Fair DA. Perinatal Western-style diet exposure associated with decreased microglial counts throughout the arcuate nucleus of the hypothalamus in Japanese macaques. J Neurophysiol 2024; 131:241-260. [PMID: 38197176 PMCID: PMC11286309 DOI: 10.1152/jn.00213.2023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2023] [Revised: 12/13/2023] [Accepted: 01/03/2024] [Indexed: 01/11/2024] Open
Abstract
Perinatal exposure to a high-fat, high-sugar Western-style diet (WSD) is associated with altered neural circuitry in the melanocortin system. This association may have an underlying inflammatory component, as consumption of a WSD during pregnancy can lead to an elevated inflammatory environment. Our group previously demonstrated that prenatal WSD exposure was associated with increased markers of inflammation in the placenta and fetal hypothalamus in Japanese macaques. In this follow-up study, we sought to determine whether this heightened inflammatory state persisted into the postnatal period, as prenatal exposure to inflammation has been shown to reprogram offspring immune function and long-term neuroinflammation would present a potential means for prolonged disruptions to microglia-mediated neuronal circuit formation. Neuroinflammation was approximated in 1-yr-old offspring by counting resident microglia and peripherally derived macrophages in the region of the hypothalamus examined in the fetal study, the arcuate nucleus (ARC). Microglia and macrophages were immunofluorescently stained with their shared marker, ionized calcium-binding adapter molecule 1 (Iba1), and quantified in 11 regions along the rostral-caudal axis of the ARC. A mixed-effects model revealed main effects of perinatal diet (P = 0.011) and spatial location (P = 0.003) on Iba1-stained cell count. Perinatal WSD exposure was associated with a slight decrease in the number of Iba1-stained cells, and cells were more densely located in the center of the ARC. These findings suggest that the heightened inflammatory state experienced in utero does not persist postnatally. This inflammatory response trajectory could have important implications for understanding how neurodevelopmental disorders progress.NEW & NOTEWORTHY Prenatal Western-style diet exposure is associated with increased microglial activity in utero. However, we found a potentially neuroprotective reduction in microglia count during early postnatal development. This trajectory could inform the timing of disruptions to microglia-mediated neuronal circuit formation. Additionally, this is the first study in juvenile macaques to characterize the distribution of microglia along the rostral-caudal axis of the arcuate nucleus of the hypothalamus. Nearby neuronal populations may be greater targets during inflammatory insults.
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Affiliation(s)
- Samantha Papadakis
- Department of Behavioral Neuroscience, Oregon Health & Science University, Portland, Oregon, United States
- Department of Psychiatry, Oregon Health & Science University, Portland, Oregon, United States
| | - Jacqueline R Thompson
- Division of Neuroscience, Oregon National Primate Research Center, Oregon Health & Science University, Beaverton, Oregon, United States
| | - Eric Feczko
- Department of Pediatrics, University of Minnesota Medical School, Minneapolis, Minnesota, United States
- Masonic Institute for the Developing Brain, University of Minnesota Medical School, Minneapolis, Minnesota, United States
| | - Oscar Miranda-Dominguez
- Department of Pediatrics, University of Minnesota Medical School, Minneapolis, Minnesota, United States
- Masonic Institute for the Developing Brain, University of Minnesota Medical School, Minneapolis, Minnesota, United States
| | - Geoffrey A Dunn
- Department of Human Physiology, University of Oregon, Eugene, Oregon, United States
| | - Matthew Selby
- Department of Human Physiology, University of Oregon, Eugene, Oregon, United States
| | - A J Mitchell
- Department of Behavioral Neuroscience, Oregon Health & Science University, Portland, Oregon, United States
- Division of Neuroscience, Oregon National Primate Research Center, Oregon Health & Science University, Beaverton, Oregon, United States
| | - Elinor L Sullivan
- Department of Behavioral Neuroscience, Oregon Health & Science University, Portland, Oregon, United States
- Department of Psychiatry, Oregon Health & Science University, Portland, Oregon, United States
- Division of Neuroscience, Oregon National Primate Research Center, Oregon Health & Science University, Beaverton, Oregon, United States
| | - Damien A Fair
- Department of Pediatrics, University of Minnesota Medical School, Minneapolis, Minnesota, United States
- Masonic Institute for the Developing Brain, University of Minnesota Medical School, Minneapolis, Minnesota, United States
- Institute of Child Development, College of Education and Human Development, University of Minnesota, Minneapolis, Minnesota, United States
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Sewaybricker LE, Huang A, Chandrasekaran S, Melhorn SJ, Schur EA. The Significance of Hypothalamic Inflammation and Gliosis for the Pathogenesis of Obesity in Humans. Endocr Rev 2023; 44:281-296. [PMID: 36251886 DOI: 10.1210/endrev/bnac023] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/20/2022] [Revised: 09/12/2022] [Indexed: 11/19/2022]
Abstract
Accumulated preclinical literature demonstrates that hypothalamic inflammation and gliosis are underlying causal components of diet-induced obesity in rodent models. This review summarizes and synthesizes available translational data to better understand the applicability of preclinical findings to human obesity and its comorbidities. The published literature in humans includes histopathologic analyses performed postmortem and in vivo neuroimaging studies measuring indirect markers of hypothalamic tissue microstructure. Both support the presence of hypothalamic inflammation and gliosis in children and adults with obesity. Findings predominantly point to tissue changes in the region of the arcuate nucleus of the hypothalamus, although findings of altered tissue characteristics in whole hypothalamus or other hypothalamic regions also emerged. Moreover, the severity of hypothalamic inflammation and gliosis has been related to comorbid conditions, including glucose intolerance, insulin resistance, type 2 diabetes, and low testosterone levels in men, independent of elevated body adiposity. Cross-sectional findings are augmented by a small number of prospective studies suggesting that a greater degree of hypothalamic inflammation and gliosis may predict adiposity gain and worsening insulin sensitivity in susceptible individuals. In conclusion, existing human studies corroborate a large preclinical literature demonstrating that hypothalamic neuroinflammatory responses play a role in obesity pathogenesis. Extensive or permanent hypothalamic tissue remodeling may negatively affect the function of neuroendocrine regulatory circuits and promote the development and maintenance of elevated body weight in obesity and/or comorbid endocrine disorders.
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Affiliation(s)
| | - Alyssa Huang
- Department of Pediatrics, University of Washington, Division of Endocrinology and Diabetes, Seattle Children's Hospital, Seattle, WA 98015, USA
| | | | - Susan J Melhorn
- Department of Medicine, University of Washington, Seattle, WA 98195, USA
| | - Ellen A Schur
- Department of Medicine, University of Washington, Seattle, WA 98195, USA
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Rosenbaum JL, Melhorn SJ, Schoen S, Webb MF, De Leon MRB, Humphreys M, Utzschneider KM, Schur EA. Evidence That Hypothalamic Gliosis Is Related to Impaired Glucose Homeostasis in Adults With Obesity. Diabetes Care 2022; 45:416-424. [PMID: 34848489 PMCID: PMC8914420 DOI: 10.2337/dc21-1535] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/23/2021] [Accepted: 11/03/2021] [Indexed: 02/03/2023]
Abstract
OBJECTIVE Preclinical research implicates hypothalamic glial cell responses in the pathogenesis of obesity and type 2 diabetes (T2D). In the current study we sought to translate such findings to humans by testing whether radiologic markers of gliosis in the mediobasal hypothalamus (MBH) were greater in individuals with obesity and impaired glucose homeostasis or T2D. RESEARCH DESIGN AND METHODS Using cross-sectional and prospective cohort study designs, we applied a validated quantitative MRI approach to assess gliosis in 67 adults with obesity and normal glucose tolerance, impaired glucose tolerance (IGT), or T2D. Assessments of glucose homeostasis were conducted via oral glucose tolerance tests (OGTT) and β-cell modeling. RESULTS We found significantly greater T2 relaxation times (a marker of gliosis by MRI), that were independent of adiposity, in the groups with IGT and T2D as compared with the group with normal glucose tolerance. Findings were present in the MBH, but not control regions. Moreover, positive linear associations were present in the MBH but not control regions between T2 relaxation time and glucose area under the curve during an OGTT, fasting glucose concentrations, hemoglobin A1c, and visceral adipose tissue mass, whereas negative linear relationships were present in the MBH for markers of insulin sensitivity and β-cell function. In a prospective cohort study, greater MBH T2 relaxation times predicted declining insulin sensitivity over 1 year. CONCLUSIONS Findings support a role for hypothalamic gliosis in the progression of insulin resistance in obesity and thus T2D pathogenesis in humans.
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Affiliation(s)
- Jennifer L Rosenbaum
- Division of Metabolism, Endocrinology and Nutrition, Department of Medicine, University of Washington, Seattle, WA
| | - Susan J Melhorn
- Division of General Internal Medicine, Department of Medicine, University of Washington, Seattle, WA.,UW Medicine Diabetes Institute, University of Washington, Seattle, WA
| | - Stefan Schoen
- University of Washington School of Medicine, Seattle, WA
| | - Mary F Webb
- Division of General Internal Medicine, Department of Medicine, University of Washington, Seattle, WA.,UW Medicine Diabetes Institute, University of Washington, Seattle, WA
| | - Mary Rosalynn B De Leon
- Division of General Internal Medicine, Department of Medicine, University of Washington, Seattle, WA.,UW Medicine Diabetes Institute, University of Washington, Seattle, WA
| | - Madelaine Humphreys
- Division of General Internal Medicine, Department of Medicine, University of Washington, Seattle, WA.,UW Medicine Diabetes Institute, University of Washington, Seattle, WA
| | - Kristina M Utzschneider
- Division of Metabolism, Endocrinology and Nutrition, Department of Medicine, University of Washington, Seattle, WA.,Research and Development, Department of Veterans Affairs, Seattle, WA
| | - Ellen A Schur
- Division of General Internal Medicine, Department of Medicine, University of Washington, Seattle, WA.,UW Medicine Diabetes Institute, University of Washington, Seattle, WA
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Huang HT, Chen PC, Chen PS, Chiu WT, Kuo YM, Tzeng SF. Inhibitory Effects of Trifluoperazine on Peripheral Proinflammatory Cytokine Expression and Hypothalamic Microglia Activation in Obese Mice Induced by Chronic Feeding With High-Fat-Diet. Front Cell Neurosci 2021; 15:752771. [PMID: 34764855 PMCID: PMC8576196 DOI: 10.3389/fncel.2021.752771] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2021] [Accepted: 10/05/2021] [Indexed: 11/13/2022] Open
Abstract
Microglia and astrocytes are the glial cells of the central nervous system (CNS) to support neurodevelopment and neuronal function. Yet, their activation in association with CNS inflammation is involved in the initiation and progression of neurological disorders. Mild inflammation in the periphery and glial activation called as gliosis in the hypothalamic region, arcuate nucleus (ARC), are generally observed in obese individuals and animal models. Thus, reduction in peripheral and central inflammation is considered as a strategy to lessen the abnormality of obesity-associated metabolic indices. In this study, we reported that acute peripheral challenge by inflammagen lipopolysaccharide (LPS) upregulated the expression of hypothalamic dopamine type 2 receptor (D2R) mRNA, and chronic feeding by high-fat-diet (HFD) significantly caused increased levels of D2R in the ARC. The in vitro and in vivo studies indicated that an FDA-approved antipsychotic drug named trifluoperazine (TFP), a D2R inhibitor was able to suppress LPS-stimulated activation of microglia and effectively inhibited LPS-induced peripheral inflammation, as well as hypothalamic inflammation. Further findings showed daily peripheral administration intraperitoneally (i.p.) by TFP for 4 weeks was able to reduce the levels of plasma tumor necrosis factor-α (TNF-α) and interleukin-1β (IL-1β) in accompany with lower levels of plasma glucose and insulin in obese mice receiving HFD for 16 weeks when compared those in obese mice without TFP treatment. In parallel, the activation of microglia and astrocytes in the ARC was also inhibited by peripheral administration by TFP. According to our results, TFP has the ability to suppress HFD-induced ARC gliosis and inflammation in the hypothalamus.
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Affiliation(s)
- Hui-Ting Huang
- Institute of Life Sciences, College of Bioscience and Biotechnology, National Cheng Kung University, Tainan, Taiwan
| | - Pei-Chun Chen
- Institute of Physiology, College of Medicine, National Cheng Kung University, Tainan, Taiwan
| | - Po-See Chen
- Department of Psychiatry, College of Medicine, National Cheng Kung University, Tainan, Taiwan
| | - Wen-Tai Chiu
- Department of Biomedical Engineering, College of Engineering, National Cheng Kung University, Tainan, Taiwan
| | - Yu-Min Kuo
- Institute of Basic Medical Sciences, Department of Cell Biology and Anatomy, College of Medicine, National Cheng Kung University, Tainan, Taiwan
| | - Shun-Fen Tzeng
- Institute of Life Sciences, College of Bioscience and Biotechnology, National Cheng Kung University, Tainan, Taiwan
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Liébana-García R, Olivares M, Bullich-Vilarrubias C, López-Almela I, Romaní-Pérez M, Sanz Y. The gut microbiota as a versatile immunomodulator in obesity and associated metabolic disorders. Best Pract Res Clin Endocrinol Metab 2021; 35:101542. [PMID: 33980476 DOI: 10.1016/j.beem.2021.101542] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Obesity has reached epidemic proportions and is associated with chronic-low-grade inflammation and metabolic morbidities. Energy-dense diets and a sedentary lifestyle are determinants of obesity. The gut microbiome is a novel biological factor involved in obesity via interactions with the host and the diet. The gut microbiome act as a synergistic force protecting or aggravating the effects of the diet on the metabolic phenotype. The role of the microbiome in the regulation of intestinal and systemic immunity is one of the mechanisms by which it contributes to the host's response to the diet and to the pathophysiology of diet-induced obesity. Here, we review the mechanisms whereby "obesogenic" diets and the microbiome impact immunity, locally and systemically, focusing on the consequences in the gut-adipose tissue axis. We also review the structural and microbial metabolites that influence immunity and how advances in this field could help design microbiome-informed strategies to tackle obesity-related disorders more effectively.
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Affiliation(s)
- Rebeca Liébana-García
- Microbial Ecology, Nutrition & Health Research Unit, Institute of Agrochemistry and Food Technology, Spanish National Research Council (IATA-CSIC), Valencia, Spain.
| | - Marta Olivares
- Microbial Ecology, Nutrition & Health Research Unit, Institute of Agrochemistry and Food Technology, Spanish National Research Council (IATA-CSIC), Valencia, Spain.
| | - Clara Bullich-Vilarrubias
- Microbial Ecology, Nutrition & Health Research Unit, Institute of Agrochemistry and Food Technology, Spanish National Research Council (IATA-CSIC), Valencia, Spain.
| | - Inmaculada López-Almela
- Microbial Ecology, Nutrition & Health Research Unit, Institute of Agrochemistry and Food Technology, Spanish National Research Council (IATA-CSIC), Valencia, Spain.
| | - Marina Romaní-Pérez
- Microbial Ecology, Nutrition & Health Research Unit, Institute of Agrochemistry and Food Technology, Spanish National Research Council (IATA-CSIC), Valencia, Spain.
| | - Yolanda Sanz
- Microbial Ecology, Nutrition & Health Research Unit, Institute of Agrochemistry and Food Technology, Spanish National Research Council (IATA-CSIC), Valencia, Spain.
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Stirm L, Kovárová M, Perschbacher S, Michlmaier R, Fritsche L, Siegel-Axel D, Schleicher E, Peter A, Pauluschke-Fröhlich J, Brucker S, Abele H, Wallwiener D, Preissl H, Wadsack C, Häring HU, Fritsche A, Ensenauer R, Desoye G, Staiger H. BMI-Independent Effects of Gestational Diabetes on Human Placenta. J Clin Endocrinol Metab 2018; 103:3299-3309. [PMID: 29931171 DOI: 10.1210/jc.2018-00397] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/19/2018] [Accepted: 06/15/2018] [Indexed: 11/19/2022]
Abstract
PURPOSE Recently, alterations in maternal lipid metabolism were associated with gestational diabetes mellitus (GDM). However, detailed plasma lipid profiles and their relevance for placental and fetal metabolism are currently not understood. METHODS Maternal and placental lipid profiles were characterized in women with GDM and women with normal glucose tolerance (NGT). Inflammatory gene expression was compared in placentas and primary term trophoblasts between the groups. In addition, trophoblasts were stimulated with nonesterified fatty acids (NEFAs), and effects on gene expression were quantified. Finally, placental macrophage content and cord blood concentrations of inflammatory parameters and NEFAs were compared between women with GDM and women with NGT with similar body mass index (BMI). RESULTS Palmitate and stearate levels were elevated in both maternal plasma and placental tissue of women with GDM. Placental GDM-associated elevations of IL6, IL8, and TLR2 expression were reflected in trophoblasts derived from women with GDM. Stimulation of primary trophoblasts with palmitate led to increased mRNA expression and protein release of the cytokine IL6 and the chemokine IL8. In line with this, elevated amounts of CD68-positive cells were quantified in the placental tissue of women with GDM. No GDM-associated elevations in a range of inflammatory parameters and NEFAs in cord blood of NGT vs GDM neonates was found. CONCLUSIONS GDM, independently of BMI, altered maternal plasma NEFAs and the placental lipid profile. GDM was associated with trophoblast and whole-placenta lipoinflammation; however, this was not accompanied by elevated concentrations of inflammatory cytokines or NEFAs in neonatal cord blood.
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Affiliation(s)
- Laura Stirm
- Institute for Diabetes Research and Metabolic Diseases of the Helmholtz Zentrum München at Eberhard Karls University Tübingen, Tübingen, Germany
- German Center for Diabetes Research, Tübingen, Germany
| | - Markéta Kovárová
- Department of Internal Medicine, Division of Endocrinology, Diabetology, Angiology, Nephrology and Clinical Chemistry, University Hospital Tübingen, Tübingen, Germany
| | - Sarah Perschbacher
- Institute for Social Pediatrics and Adolescent Medicine, Ludwig-Maximilians-Universität München, Munich, Germany
| | - Renate Michlmaier
- Department of Obstetrics and Gynaecology, Medical University of Graz, Graz, Austria
| | - Louise Fritsche
- Institute for Diabetes Research and Metabolic Diseases of the Helmholtz Zentrum München at Eberhard Karls University Tübingen, Tübingen, Germany
- German Center for Diabetes Research, Tübingen, Germany
| | - Dorothea Siegel-Axel
- Institute for Diabetes Research and Metabolic Diseases of the Helmholtz Zentrum München at Eberhard Karls University Tübingen, Tübingen, Germany
- German Center for Diabetes Research, Tübingen, Germany
- Department of Internal Medicine, Division of Endocrinology, Diabetology, Angiology, Nephrology and Clinical Chemistry, University Hospital Tübingen, Tübingen, Germany
| | - Erwin Schleicher
- Institute for Diabetes Research and Metabolic Diseases of the Helmholtz Zentrum München at Eberhard Karls University Tübingen, Tübingen, Germany
- German Center for Diabetes Research, Tübingen, Germany
- Department of Internal Medicine, Division of Endocrinology, Diabetology, Angiology, Nephrology and Clinical Chemistry, University Hospital Tübingen, Tübingen, Germany
| | - Andreas Peter
- Institute for Diabetes Research and Metabolic Diseases of the Helmholtz Zentrum München at Eberhard Karls University Tübingen, Tübingen, Germany
- German Center for Diabetes Research, Tübingen, Germany
- Department of Internal Medicine, Division of Endocrinology, Diabetology, Angiology, Nephrology and Clinical Chemistry, University Hospital Tübingen, Tübingen, Germany
| | | | - Sara Brucker
- Department of Obstetrics and Gynaecology, University Hospital Tübingen, Tübingen, Germany
| | - Harald Abele
- Department of Obstetrics and Gynaecology, University Hospital Tübingen, Tübingen, Germany
| | - Diethelm Wallwiener
- Department of Obstetrics and Gynaecology, University Hospital Tübingen, Tübingen, Germany
| | - Hubert Preissl
- Institute for Diabetes Research and Metabolic Diseases of the Helmholtz Zentrum München at Eberhard Karls University Tübingen, Tübingen, Germany
- German Center for Diabetes Research, Tübingen, Germany
- Department of Internal Medicine, Division of Endocrinology, Diabetology, Angiology, Nephrology and Clinical Chemistry, University Hospital Tübingen, Tübingen, Germany
- Institute for Diabetes and Obesity, Helmholtz Diabetes Center, Helmholtz Zentrum München, Munich, Germany
- Institute of Pharmaceutical Sciences, Department of Pharmacy and Biochemistry, Eberhard Karls University Tübingen, Tübingen, Germany
| | - Christian Wadsack
- Department of Obstetrics and Gynaecology, Medical University of Graz, Graz, Austria
| | - Hans-Ulrich Häring
- Institute for Diabetes Research and Metabolic Diseases of the Helmholtz Zentrum München at Eberhard Karls University Tübingen, Tübingen, Germany
- German Center for Diabetes Research, Tübingen, Germany
- Department of Internal Medicine, Division of Endocrinology, Diabetology, Angiology, Nephrology and Clinical Chemistry, University Hospital Tübingen, Tübingen, Germany
| | - Andreas Fritsche
- Institute for Diabetes Research and Metabolic Diseases of the Helmholtz Zentrum München at Eberhard Karls University Tübingen, Tübingen, Germany
- German Center for Diabetes Research, Tübingen, Germany
- Department of Internal Medicine, Division of Endocrinology, Diabetology, Angiology, Nephrology and Clinical Chemistry, University Hospital Tübingen, Tübingen, Germany
| | - Regina Ensenauer
- Institute for Social Pediatrics and Adolescent Medicine, Ludwig-Maximilians-Universität München, Munich, Germany
- Division of Experimental Pediatrics and Metabolism, University Children's Hospital, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
| | - Gernot Desoye
- Department of Obstetrics and Gynaecology, Medical University of Graz, Graz, Austria
| | - Harald Staiger
- Institute for Diabetes Research and Metabolic Diseases of the Helmholtz Zentrum München at Eberhard Karls University Tübingen, Tübingen, Germany
- German Center for Diabetes Research, Tübingen, Germany
- Institute of Pharmaceutical Sciences, Department of Pharmacy and Biochemistry, Eberhard Karls University Tübingen, Tübingen, Germany
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King A, Brain A, Hanson K, Dittmann J, Vickers J, Fernandez-Martos C. Disruption of leptin signalling in a mouse model of Alzheimer's disease. Metab Brain Dis 2018; 33:1097-1110. [PMID: 29546689 DOI: 10.1007/s11011-018-0203-9] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/21/2017] [Accepted: 02/15/2018] [Indexed: 12/12/2022]
Abstract
Disruption of leptin signalling has been implicated as playing a role in the development of Alzheimer's disease (AD). Leptin has previously been shown to be affected by amyloid-beta (Aβ)-related signalling; however, pathways that link leptin to the disease pathogenesis have not been determined. To characterize the association between increasing age-dependent Aβ levels with leptin signalling and the vulnerable brain regions in AD, we assessed the mRNA and protein expression profile of leptin and leptin receptor (Ob-Rb) at 9 and 18-month-age in APP/PS1 mice. Immunohistochemical labelling demonstrated that leptin and Ob-Rb proteins were localised to neocortical and hippocampal neurons in APP/PS1 and wildtype (WT) mice. Neuronal leptin and Ob-Rb immunolabelling was more prominent in the neocortex of both groups at 9 month of age, while, at 18 months, labelling was reduced in the hippocampus of APP/PS1 mice relative to WT. Immunoblotting analysis demonstrated decreased hippocampal leptin levels, concomitantly with an increased Ob-Rb levels, in APP/PS1 mice compared with WT controls at 18 month of age. While no leptin mRNA was found in either of the groups analysed, Ob-Rb mRNA was significantly decreased in the hippocampus of APP/PS1 mice at both ages analysed. In addition, a significant decreased protein kinase B (Akt) activity concomitantly with an upregulation of suppressor of cytokine signaling-3 (SOCS3) and protein-tyrosine phosphatase 1B (PTP1B) transcripts was present. Thus, these results collectively indicate alterations of leptin signalling in the hippocampus of APP/PS1 mice, providing novel insights about the pathways that could link aberrant leptin signaling to the pathological changes of AD.
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Affiliation(s)
- Anna King
- Wicking Dementia Research and Education Centre, Faculty of Health, University of Tasmania, Private Bag 143, Hobart, TAS, 7000, Australia
| | - Anna Brain
- Wicking Dementia Research and Education Centre, Faculty of Health, University of Tasmania, Private Bag 143, Hobart, TAS, 7000, Australia
| | - Kelsey Hanson
- Wicking Dementia Research and Education Centre, Faculty of Health, University of Tasmania, Private Bag 143, Hobart, TAS, 7000, Australia
| | - Justin Dittmann
- Wicking Dementia Research and Education Centre, Faculty of Health, University of Tasmania, Private Bag 143, Hobart, TAS, 7000, Australia
| | - James Vickers
- Wicking Dementia Research and Education Centre, Faculty of Health, University of Tasmania, Private Bag 143, Hobart, TAS, 7000, Australia
| | - Carmen Fernandez-Martos
- Wicking Dementia Research and Education Centre, Faculty of Health, University of Tasmania, Private Bag 143, Hobart, TAS, 7000, Australia.
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Li M, Sirko S. Traumatic Brain Injury: At the Crossroads of Neuropathology and Common Metabolic Endocrinopathies. J Clin Med 2018. [PMID: 29538298 PMCID: PMC5867585 DOI: 10.3390/jcm7030059] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Building on the seminal work by Geoffrey Harris in the 1970s, the neuroendocrinology field, having undergone spectacular growth, has endeavored to understand the mechanisms of hormonal connectivity between the brain and the rest of the body. Given the fundamental role of the brain in the orchestration of endocrine processes through interactions among neurohormones, it is thus not surprising that the structural and/or functional alterations following traumatic brain injury (TBI) can lead to endocrine changes affecting the whole organism. Taking into account that systemic hormones also act on the brain, modifying its structure and biochemistry, and can acutely and chronically affect several neurophysiological endpoints, the question is to what extent preexisting endocrine dysfunction may set the stage for an adverse outcome after TBI. In this review, we provide an overview of some aspects of three common metabolic endocrinopathies, e.g., diabetes mellitus, obesity, and thyroid dysfunction, and how these could be triggered by TBI. In addition, we discuss how the complex endocrine networks are woven into the responses to sudden changes after TBI, as well as some of the potential mechanisms that, separately or synergistically, can influence outcomes after TBI.
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Affiliation(s)
- Melanie Li
- Physiological Genomics, Biomedical Center (BMC), Institute of Physiology, Medical Faculty of the Ludwig-Maximilian University Munich, 82152 Planegg-Martinsried, Germany.
| | - Swetlana Sirko
- Physiological Genomics, Biomedical Center (BMC), Institute of Physiology, Medical Faculty of the Ludwig-Maximilian University Munich, 82152 Planegg-Martinsried, Germany.
- Institute of Stem Cell Research, Helmholtz Center Munich, Research Center for Environmental Health GmbH, 85764 Neuherberg, Germany.
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9
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Kalsbeek MJT, Mulder L, Yi CX. Microglia energy metabolism in metabolic disorder. Mol Cell Endocrinol 2016; 438:27-35. [PMID: 27687525 DOI: 10.1016/j.mce.2016.09.028] [Citation(s) in RCA: 49] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/20/2016] [Revised: 09/23/2016] [Accepted: 09/26/2016] [Indexed: 12/22/2022]
Abstract
Microglia are the resident macrophages of the CNS, and are in charge of maintaining a healthy microenvironment to ensure neuronal survival. Microglia carry out a non-stop patrol of the CNS, make contact with neurons and look for abnormalities, all of which requires a vast amount of energy. This non-signaling energy demand increases after activation by pathogens, neuronal damage or other kinds of stimulation. Of the three major energy substrates - glucose, fatty acids and glutamine - glucose is crucial for microglia survival and several glucose transporters are expressed to supply sufficient glucose influx. Fatty acids are another source of energy for microglia and have also been shown to strongly influence microglial immune activity. Glutamine, although possibly suitable for use as an energy substrate by microglia, has been shown to have neurotoxic effects when overloaded. Microglial fuel metabolism might be associated with microglial reactivity under different pathophysiological conditions and a microglial fuel switch may thus be the underlying cause of hypothalamic dysregulation, which is associated with obesity.
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Affiliation(s)
- Martin J T Kalsbeek
- Department of Endocrinology and Metabolism, Academic Medical Center (AMC), University of Amsterdam (UvA), Meibergdreef 9, 1105 AZ, Amsterdam, The Netherlands.
| | - Laurie Mulder
- Department of Endocrinology and Metabolism, Academic Medical Center (AMC), University of Amsterdam (UvA), Meibergdreef 9, 1105 AZ, Amsterdam, The Netherlands
| | - Chun-Xia Yi
- Department of Endocrinology and Metabolism, Academic Medical Center (AMC), University of Amsterdam (UvA), Meibergdreef 9, 1105 AZ, Amsterdam, The Netherlands
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Hofmann K, Lamberz C, Piotrowitz K, Offermann N, But D, Scheller A, Al-Amoudi A, Kuerschner L. Tanycytes and a differential fatty acid metabolism in the hypothalamus. Glia 2016; 65:231-249. [PMID: 27726181 DOI: 10.1002/glia.23088] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2016] [Revised: 08/31/2016] [Accepted: 09/28/2016] [Indexed: 11/12/2022]
Abstract
Although the brain controls all main metabolic pathways in the whole organism, its lipid metabolism is partially separated from the rest of the body. Circulating lipids and other metabolites are taken up into brain areas like the hypothalamus and are locally metabolized and sensed involving several hypothalamic cell types. In this study we show that saturated and unsaturated fatty acids are differentially processed in the murine hypothalamus. The observed differences involve both lipid distribution and metabolism. Key findings were: (i) hypothalamic astrocytes are targeted by unsaturated, but not saturated lipids in lean mice; (ii) in obese mice labeling of these astrocytes by unsaturated oleic acid cannot be detected unless β-oxidation or ketogenesis is inhibited; (iii) the hypothalamus of obese animals increases ketone body and neutral lipid synthesis while tanycytes, hypothalamic cells facing the ventricle, increase their lipid droplet content; and (iv) tanycytes show different labeling for saturated or unsaturated lipids. Our data support a metabolic connection between tanycytes and astrocytes likely to impact hypothalamic lipid sensing. GLIA 2017;65:231-249.
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Affiliation(s)
- Kristina Hofmann
- Life and Medical Sciences Institute (LIMES), University of Bonn, Bonn, D-53115, Germany
| | - Christian Lamberz
- German Center for Neurodegenerative Diseases (DZNE), Bonn, D-53175, Germany
| | - Kira Piotrowitz
- Life and Medical Sciences Institute (LIMES), University of Bonn, Bonn, D-53115, Germany
| | - Nina Offermann
- Life and Medical Sciences Institute (LIMES), University of Bonn, Bonn, D-53115, Germany
| | - Diana But
- Life and Medical Sciences Institute (LIMES), University of Bonn, Bonn, D-53115, Germany
| | - Anja Scheller
- Department of Molecular Physiology, Center for Integrative Physiology and Molecular Medicine (CIPMM), University of Saarland, Homburg, D-66421, Germany
| | - Ashraf Al-Amoudi
- German Center for Neurodegenerative Diseases (DZNE), Bonn, D-53175, Germany
| | - Lars Kuerschner
- Life and Medical Sciences Institute (LIMES), University of Bonn, Bonn, D-53115, Germany
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Metabolic and behavioral effects of mutant huntingtin deletion in Sim1 neurons in the BACHD mouse model of Huntington's disease. Sci Rep 2016; 6:28322. [PMID: 27334347 PMCID: PMC4917832 DOI: 10.1038/srep28322] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2016] [Accepted: 05/31/2016] [Indexed: 02/06/2023] Open
Abstract
Hypothalamic pathology, metabolic dysfunction and psychiatric symptoms are part of Huntington disease (HD), which is caused by an expanded CAG repeat in the huntingtin (HTT) gene. Inactivation of mutant HTT selectively in the hypothalamus prevents the development of metabolic dysfunction and depressive-like behavior in the BACHD mouse model. The hypothalamic paraventricular nucleus (PVN) is implicated in metabolic and emotional control, therefore we here tested whether inactivation of mutant HTT in the PVN affects metabolic and psychiatric manifestations of HD in BACHD mice. BACHD mice were crossed with mice expressing Cre-recombinase under the Sim1 promoter (Sim1-Cre) to inactivate mutant HTT in Sim1 expressing cells, i.e. the PVN of the hypothalamus. We found that inactivation of mutant HTT in Sim1 cells had a sex-specific effect on both the metabolic and the psychiatric phenotype, as these phenotypes were no longer different in male BACHD/Sim1-Cre mice compared to wild-type littermates. We also found a reduced number of GnRH neurons specifically in the anterior hypothalamus and an increased testes weight in male BACHD mice compared to wild-type littermates. Taken together, expression of mutant HTT in Sim1 cells may play a role for the development of metabolic dysfunction and depressive-like behavior in male BACHD mice.
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12
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Diversity and plasticity of microglial cells in psychiatric and neurological disorders. Pharmacol Ther 2015; 154:21-35. [DOI: 10.1016/j.pharmthera.2015.06.010] [Citation(s) in RCA: 106] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2015] [Accepted: 06/25/2015] [Indexed: 02/07/2023]
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13
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Greenway FL. Physiological adaptations to weight loss and factors favouring weight regain. Int J Obes (Lond) 2015; 39:1188-96. [PMID: 25896063 PMCID: PMC4766925 DOI: 10.1038/ijo.2015.59] [Citation(s) in RCA: 257] [Impact Index Per Article: 28.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/17/2014] [Revised: 03/24/2015] [Accepted: 04/04/2015] [Indexed: 02/07/2023]
Abstract
Obesity is a major global health problem and predisposes individuals to several comorbidities that can affect life expectancy. Interventions based on lifestyle modification (for example, improved diet and exercise) are integral components in the management of obesity. However, although weight loss can be achieved through dietary restriction and/or increased physical activity, over the long term many individuals regain weight. The aim of this article is to review the research into the processes and mechanisms that underpin weight regain after weight loss and comment on future strategies to address them. Maintenance of body weight is regulated by the interaction of a number of processes, encompassing homoeostatic, environmental and behavioural factors. In homoeostatic regulation, the hypothalamus has a central role in integrating signals regarding food intake, energy balance and body weight, while an 'obesogenic' environment and behavioural patterns exert effects on the amount and type of food intake and physical activity. The roles of other environmental factors are also now being considered, including sleep debt and iatrogenic effects of medications, many of which warrant further investigation. Unfortunately, physiological adaptations to weight loss favour weight regain. These changes include perturbations in the levels of circulating appetite-related hormones and energy homoeostasis, in addition to alterations in nutrient metabolism and subjective appetite. To maintain weight loss, individuals must adhere to behaviours that counteract physiological adaptations and other factors favouring weight regain. It is difficult to overcome physiology with behaviour. Weight loss medications and surgery change the physiology of body weight regulation and are the best chance for long-term success. An increased understanding of the physiology of weight loss and regain will underpin the development of future strategies to support overweight and obese individuals in their efforts to achieve and maintain weight loss.
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Affiliation(s)
- F L Greenway
- Pennington Biomedical Research Center, Louisiana State University System, Baton Rouge, LA, USA
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Sasaki T. Age-Associated Weight Gain, Leptin, and SIRT1: A Possible Role for Hypothalamic SIRT1 in the Prevention of Weight Gain and Aging through Modulation of Leptin Sensitivity. Front Endocrinol (Lausanne) 2015; 6:109. [PMID: 26236282 PMCID: PMC4504171 DOI: 10.3389/fendo.2015.00109] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/24/2015] [Accepted: 07/01/2015] [Indexed: 12/14/2022] Open
Abstract
The hypothalamus is the principal regulator of body weight and energy balance. It modulates both energy intake and energy expenditure by sensing the energy status of the body through neural inputs from the periphery as well as direct humoral inputs. Leptin, an adipokine, is one of the humoral factors responsible for alerting the hypothalamus that enough energy is stored in the periphery. Plasma leptin levels are positively linked to adiposity; leptin suppress energy intake and stimulates energy expenditure. However, prolonged increases in plasma leptin levels due to obesity cause leptin resistance, affecting both leptin access to hypothalamic neurons and leptin signal transduction within hypothalamic neurons. Decreased sensing of peripheral energy status through leptin may lead to a positive energy balance and gradual gains in weight and adiposity, further worsening leptin resistance. Leptin resistance, increased adiposity, and weight gain are all associated with aging in both humans and animals. Central insulin resistance is associated with similar observations. Therefore, improving the action of humoral factors in the hypothalamus may prevent gradual weight gain, especially during middle age. SIRT1 is a NAD(+)-dependent protein deacetylase with numerous substrates, including histones, transcription factors, co-factors, and various enzymes. SIRT1 improves both leptin sensitivity and insulin sensitivity by decreasing the levels of several molecules that impair leptin and insulin signal transduction. SIRT1 and NAD(+) levels decrease with age in the hypothalamus; increased hypothalamic SIRT1 levels prevent age-associated weight gain and improve leptin sensitivity in mice. Therefore, preventing the age-dependent loss of SIRT1 function in the hypothalamus could improve the action of humoral factors in the hypothalamus as well as central regulation of energy balance.
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Affiliation(s)
- Tsutomu Sasaki
- Laboratory for Metabolic Signaling, Institute for Molecular and Cellular Regulation, Gunma University, Maebashi, Japan
- *Correspondence: Tsutomu Sasaki, Laboratory for Metabolic Signaling, Institute for Molecular and Cellular Regulation, Gunma University, 3-39-15 Showa-machi, Maebashi, Gunma 371-8512, Japan,
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